FRESNO, Calif. (KFSN) -- One in nine American babies is born prematurely, and the tiniest of those babies often spend weeks, or months in specialized neo-natal intensive care units, or NICUs. One of the biggest threats to these preemies is an infection that "eats away" their intestines. Researchers are studying the balance of bacteria in these babies' guts to see if they can stop the deadly infection before it does any damage.

Grayson Winters is a chubby-cheeked 1-year old. It's hard to imagine him at 1 lb., 15oz., born 16 weeks early.

Four weeks after Grayson was born he developed an infection in his intestines called necrotizing enterocolitis or NEC.

"He had to have part of his intestines removed and he had a colostomy bag," Winters told ABC30.

NEC affects between five and12 percent of preemies born before 34 weeks gestation. Twenty to 30 percent of the babies who get NEC will die from it. In the most premature of babies, up to 50 percent who get it, die.

"I always feel like necrotizing enterocolitis is like Russian roulette," Barbara Warner, M.D., Neonatologist and Professor of Pediatrics in the Division of Newborn Medicine at Washington University School of Medicine in St. Louis, told ABC30.

Dr. Barbara Warner studies microbes that occur naturally in the gut. Researchers believe babies are born with pristine digestive systems, and then their guts become filled with good and bad microbes. Researchers say the types of bacteria present in the gut of preemies are different from those found in healthy term infants, and the rate of bacteria growth is linked to gestational age.

"Clearly if we can identify a signature for NEC we can intervene potentially earlier," said Dr. Warner.

Grayson's intestines are functioning normally again. The only side effect, fading scars on his belly.

Winters said, "I think there's life after NEC."

Dr. Warner says the use of breast milk is one of the ways researchers have been able to decrease the incidence of "NEC." They are continuing to study the ways different diets affect gut microbes.